1. Field of the Invention
The invention relates to a method and an engineering system with which relationships between Computer Aided Design (CAD) objects in different CAD models can be automatically identified. The invention is of use particularly in interactive planning and engineering processes in which CAD models are produced at different levels of abstraction.
2. Description of the Related Art
The use of CAD, Computer Aided Engineering (CAE) or Computer Aided Manufacturing (CAM) programs is widespread in the field of digital product and factory planning. In the planning, manufacture, and down to any maintenance tasks which may arise, an attempt is made to provide an information-technological accompaniment for the life cycle of a product, over its complete life cycle. In doing so, the aim is for an integrated approach, in which the data storage is as far as possible uniform, from planning, through realization, control and ongoing improvements of all the important factory processes and resources connected with the product.
Correspondingly, during the planning process described above many CAD models are produced for individual special domains, such as factory planning, assembly instructions or simulations. Here, the CAD models are optimized for the purpose of their particular use. The applications employed for this often also require data from other applications which work with CAD models. To make this possible, it is desirable that the data from the various source systems, which are used in a planning process, is brought together centrally and stored in synchronized form. To this end, engineering systems at a higher level than the individual sources systems are employed. Within these engineering systems, the user has an option to build up a so-called resource structure. This resource structure consists of resource labels, which are assigned to each of the CAD objects concerned, and with which the user can access these CAD objects. If, for example, the same physical component is modeled by two different CAD objects, which in some circumstances originate in different CAD systems, then the user can assign a shared resource label to both these CAD objects. In this way, the two CAD objects are brought together in the engineering system, thereby making it possible to synchronize the data which underlies the CAD objects.
If an industrial automation system is being planned with the tools of a digital factory, then the physical components used give rise to CAD models at various levels of abstraction. At a very early phase of the planning, extensive systems are often represented by a CAD object which is still relatively coarse in nature. As the planning phase proceeds, this CAD object is then often specified more precisely in that individual components of the system which is being modeled are each represented by a CAD object which is richer in detail. In many cases, this will be achieved using a CAD tool other than that which was used in the early phase of the project.
Consequently, in the course of such a planning operation, new CAD objects are produced which have, along with the coarser CAD objects generated at the start, a sort of group relationship based on the spatial connection between the components modeled. A user who identifies such a group relationship now has the possibility to make such knowledge accessible to an engineering system. The user can thus, for example, within the engineering system set up a resource for the system which is to be modeled and, subordinate to this, define sub-resources assigned to the relevant components of the automaton system that are modeled by CAD objects.